Rapid detection of cowpea aphid-borne mosaic virus in cowpea seeds

Four cultivars of cowpea (Vigna unguiculata [L]. Walp.) were infected with cowpea aphid-borne mosaic virus (CABMV) by natural infection in field plots. Seeds taken from these plants were tested for the presence of the virus by ELISA and symptom observation on the plantlets grown from the seeds. A biotin/ streptavidin ELISA technique was used and found to be more sensitive than a standard ELISA protocol for detecting CABMV infection in seed. There was a good correlation between the ELISA detection of CABMV in tissue taken from single cowpea seeds and subsequent development of infected plants grown from the same seeds. The ELISA technique is reliable for selecting CABMV-free stocks of cowpea seeds.